Gas turbine engines, such as turbofan engines for an aircraft, may include a fan section, a compression section, a combustion section, and a turbine section. The fan section may include a rotor assembly and a stator assembly. The rotor assembly of the fan may further include a fan hub and a plurality of outwardly extending airfoils. Each airfoil may include a blade portion, a root portion, and a platform. The blade portion of the airfoil may extend through the flow path and interact with the gases in the flow path to transfer energy between the rotor assembly and the gases. The platform typically extends circumferentially from the rotor blade to an adjacent rotor blade and is disposed radially between the blade portion and the root portion. The stator assembly may include a fan case, which circumscribes the rotor assembly in close proximity to the tips of the blades.
During operation, the fan draws the gases (air) into the engine. The fan (driven by the turbine) raises the pressure of this air, thus producing useful thrust. Improvements in fan performance depend in many cases on reducing fluid flow leakage at various points in the fan. One of these places is between adjacent fan blades at the inner radial portions thereof near the fan hub. Typically, platforms are utilized to seal this gap and to form the inner fan air flow path between the fan blades.
Platforms assemblies may be created from stock along with the fan blade. Rubber flap seals may then seal the gaps between adjacent fairing assemblies. As fan blades are typically constructed of alloys, machining the platform assembly from stock is expensive and time consuming. Alternative materials, such as composite materials, may be used to form platforms. However, the alternative materials may be subject to flexion and deformation depending on the material strength.